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Since the earliest days of animation, two-dimensional (2D) animation has been created by presenting a series of drawings to the viewer in rapid succession where each drawing was similar to but slightlydifferent from the previous drawing. Because of the property of human vision to blur one Image Into the next, if the images are sufficiently similar and theyare presented in rapid succession, the human mind perceives the series of images as continuous motion. This is how motion pictures work, and it is also how thecartoons that you see on television work.


Animation can be created in a couple of different ways in Scratch. One way is through the use of something called costumes . For example, when you createa new project in Scratch, an image of a cat having two costumes is automatically added to the project. Image D shows a screen shot of the center panel in the user interface for a new project with the Costumes tab selected.

Image d. the costumes tab for a new scratch project.

Missing image.
Image D. The costumes tab for a new Scratch project.

Image D shows a lot more than just the current costumes. The current costumes are shown in the upper-left corner of Image D .

The cat sprite has two costumes

As you can see, the cat sprite has two costumes, which are really two different images of the cat. The images are designed to make it look like thecat is walking if the two images are repeated in rapid succession. You can also see that each costume has a name, with the default names in this case being:

  • costume1
  • costume2

If you choose to do so, you can click in the boxes containing the names and modify them. Also, if you choose to do so, you can use the built-in drawing program to modifythe drawing. However, most of that is beyond the scope of this module so we won't get into it here.

With only two costumes for the cat, the walking motion is not very smooth. Somewhere on the Scratch website, I saw a project that had sixteendifferent costumes for the cat. When those sixteen different costumes are displayed in succession, the cat appears to walk very smoothly.

Loop blocks

If you click the tan Control button in the Scratch user interface, you will expose a large number of blocks that are generally used to control the flow of the program. The following control blocks that areexposed by that button can be used to construct loops:

repeat (numeric value) - (see

The repeat (numeric value) block

The repeat (numeric value) block (referred to hereafter simply as the repeat block) provides the mechanism by which you can cause a set of actions to be executed a specified number of times. (See Image E .)

You create a repeat block that will do something useful by inserting programming blocks into the mouth of a repeat block. When you drag a raw repeat block into the center panel, it looks like the tan image shown in Image E .

Image e. various scratch blocks.

Missing image.
Image E. Various Scratch blocks.

Setting the number of repeats (iterations)

By default, the white box in the repeat block contains a literal numeric value. You can modify that value and specify the number of times thatthe code in the repeat block will be executed. When you use a literal value, the code will be executed the same number of times every time you run theprogram.

Questions & Answers

find the 15th term of the geometric sequince whose first is 18 and last term of 387
Jerwin Reply
The given of f(x=x-2. then what is the value of this f(3) 5f(x+1)
virgelyn Reply
hmm well what is the answer
how do they get the third part x = (32)5/4
kinnecy Reply
can someone help me with some logarithmic and exponential equations.
Jeffrey Reply
sure. what is your question?
okay, so you have 6 raised to the power of 2. what is that part of your answer
I don't understand what the A with approx sign and the boxed x mean
it think it's written 20/(X-6)^2 so it's 20 divided by X-6 squared
I'm not sure why it wrote it the other way
I got X =-6
ok. so take the square root of both sides, now you have plus or minus the square root of 20= x-6
oops. ignore that.
so you not have an equal sign anywhere in the original equation?
is it a question of log
Commplementary angles
Idrissa Reply
im all ears I need to learn
right! what he said ⤴⤴⤴
what is a good calculator for all algebra; would a Casio fx 260 work with all algebra equations? please name the cheapest, thanks.
Kevin Reply
a perfect square v²+2v+_
Dearan Reply
kkk nice
Abdirahman Reply
algebra 2 Inequalities:If equation 2 = 0 it is an open set?
Kim Reply
or infinite solutions?
The answer is neither. The function, 2 = 0 cannot exist. Hence, the function is undefined.
Embra Reply
if |A| not equal to 0 and order of A is n prove that adj (adj A = |A|
Nancy Reply
rolling four fair dice and getting an even number an all four dice
ramon Reply
Kristine 2*2*2=8
Bridget Reply
Differences Between Laspeyres and Paasche Indices
Emedobi Reply
No. 7x -4y is simplified from 4x + (3y + 3x) -7y
Mary Reply
how do you translate this in Algebraic Expressions
linda Reply
Need to simplify the expresin. 3/7 (x+y)-1/7 (x-1)=
Crystal Reply
. After 3 months on a diet, Lisa had lost 12% of her original weight. She lost 21 pounds. What was Lisa's original weight?
Chris Reply
what's the easiest and fastest way to the synthesize AgNP?
Damian Reply
types of nano material
abeetha Reply
I start with an easy one. carbon nanotubes woven into a long filament like a string
many many of nanotubes
what is the k.e before it land
what is the function of carbon nanotubes?
I'm interested in nanotube
what is nanomaterials​ and their applications of sensors.
Ramkumar Reply
what is nano technology
Sravani Reply
what is system testing?
preparation of nanomaterial
Victor Reply
Yes, Nanotechnology has a very fast field of applications and their is always something new to do with it...
Himanshu Reply
good afternoon madam
what is system testing
what is the application of nanotechnology?
In this morden time nanotechnology used in many field . 1-Electronics-manufacturad IC ,RAM,MRAM,solar panel etc 2-Helth and Medical-Nanomedicine,Drug Dilivery for cancer treatment etc 3- Atomobile -MEMS, Coating on car etc. and may other field for details you can check at Google
anybody can imagine what will be happen after 100 years from now in nano tech world
after 100 year this will be not nanotechnology maybe this technology name will be change . maybe aftet 100 year . we work on electron lable practically about its properties and behaviour by the different instruments
name doesn't matter , whatever it will be change... I'm taking about effect on circumstances of the microscopic world
how hard could it be to apply nanotechnology against viral infections such HIV or Ebola?
silver nanoparticles could handle the job?
not now but maybe in future only AgNP maybe any other nanomaterials
I'm interested in Nanotube
this technology will not going on for the long time , so I'm thinking about femtotechnology 10^-15
can nanotechnology change the direction of the face of the world
Prasenjit Reply
At high concentrations (>0.01 M), the relation between absorptivity coefficient and absorbance is no longer linear. This is due to the electrostatic interactions between the quantum dots in close proximity. If the concentration of the solution is high, another effect that is seen is the scattering of light from the large number of quantum dots. This assumption only works at low concentrations of the analyte. Presence of stray light.
Ali Reply
the Beer law works very well for dilute solutions but fails for very high concentrations. why?
bamidele Reply
how did you get the value of 2000N.What calculations are needed to arrive at it
Smarajit Reply
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Source:  OpenStax, Teaching beginners to code. OpenStax CNX. May 27, 2013 Download for free at http://cnx.org/content/col11498/1.20
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